problems/day22.html

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  16 Oh, hello!  Funny seeing you here.
  17
  18 I appreciate your enthusiasm, but you aren't going to find much down here.
  19 There certainly aren't clues to any of the puzzles.  The best surprises don't
  20 even appear in the source until you unlock them for real.
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  22 Please be careful with automated requests; I'm not a massive company, and I can
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  25 If you're curious about how Advent of Code works, it's running on some custom
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  28 of the puzzles.
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  30 The puzzles are most of the work; preparing a new calendar and a new set of
  31 puzzles each year takes all of my free time for 4-5 months. A lot of effort
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  37 - Eric Wastl
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  90 <header><div><h1 class="title-global"><a href="/">Advent of Code</a></h1><nav><ul><li><a href="/2021/about">[About]</a></li><li><a href="/2021/events">[Events]</a></li><li><a href="https://teespring.com/stores/advent-of-code" target="_blank">[Shop]</a></li><li><a href="/2021/settings">[Settings]</a></li><li><a href="/2021/auth/logout">[Log Out]</a></li></ul></nav><div class="user">Neil Smith <a href="/2021/support" class="supporter-badge" title="Advent of Code Supporter">(AoC++)</a> <span class="star-count">44*</span></div></div><div><h1 class="title-event">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span class="title-event-wrap">λy.</span><a href="/2021">2021</a><span class="title-event-wrap"></span></h1><nav><ul><li><a href="/2021">[Calendar]</a></li><li><a href="/2021/support">[AoC++]</a></li><li><a href="/2021/sponsors">[Sponsors]</a></li><li><a href="/2021/leaderboard">[Leaderboard]</a></li><li><a href="/2021/stats">[Stats]</a></li></ul></nav></div></header>
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  98 <article class="day-desc"><h2>--- Day 22: Reactor Reboot ---</h2><p>Operating at these extreme ocean depths has overloaded the submarine's reactor; it needs to be rebooted.</p>
  99 <p>The reactor core is made up of a large 3-dimensional grid made up entirely of cubes, one cube per integer 3-dimensional coordinate (<code>x,y,z</code>). Each cube can be either <em>on</em> or <em>off</em>; at the start of the reboot process, they are all <em>off</em>. (Could it be an old model of a reactor you've seen <a href="/2020/day/17">before</a>?)</p>
 100 <p>To reboot the reactor, you just need to set all of the cubes to either <em>on</em> or <em>off</em> by following a list of <em>reboot steps</em> (your puzzle input). Each step specifies a <a href="https://en.wikipedia.org/wiki/Cuboid" target="_blank">cuboid</a> (the set of all cubes that have coordinates which fall within ranges for <code>x</code>, <code>y</code>, and <code>z</code>) and whether to turn all of the cubes in that cuboid <em>on</em> or <em>off</em>.</p>
 101 <p>For example, given these reboot steps:</p>
 102 <pre><code>on x=10..12,y=10..12,z=10..12
 103 on x=11..13,y=11..13,z=11..13
 104 off x=9..11,y=9..11,z=9..11
 105 on x=10..10,y=10..10,z=10..10
 106 </code></pre>
 107 <p>The first step (<code>on x=10..12,y=10..12,z=10..12</code>) turns <em>on</em> a 3x3x3 cuboid consisting of 27 cubes:</p>
 108 <ul>
 109 <li><code>10,10,10</code></li>
 110 <li><code>10,10,11</code></li>
 111 <li><code>10,10,12</code></li>
 112 <li><code>10,11,10</code></li>
 113 <li><code>10,11,11</code></li>
 114 <li><code>10,11,12</code></li>
 115 <li><code>10,12,10</code></li>
 116 <li><code>10,12,11</code></li>
 117 <li><code>10,12,12</code></li>
 118 <li><code>11,10,10</code></li>
 119 <li><code>11,10,11</code></li>
 120 <li><code>11,10,12</code></li>
 121 <li><code>11,11,10</code></li>
 122 <li><code>11,11,11</code></li>
 123 <li><code>11,11,12</code></li>
 124 <li><code>11,12,10</code></li>
 125 <li><code>11,12,11</code></li>
 126 <li><code>11,12,12</code></li>
 127 <li><code>12,10,10</code></li>
 128 <li><code>12,10,11</code></li>
 129 <li><code>12,10,12</code></li>
 130 <li><code>12,11,10</code></li>
 131 <li><code>12,11,11</code></li>
 132 <li><code>12,11,12</code></li>
 133 <li><code>12,12,10</code></li>
 134 <li><code>12,12,11</code></li>
 135 <li><code>12,12,12</code></li>
 136 </ul>
 137 <p>The second step (<code>on x=11..13,y=11..13,z=11..13</code>) turns <em>on</em> a 3x3x3 cuboid that overlaps with the first. As a result, only 19 additional cubes turn on; the rest are already on from the previous step:</p>
 138 <ul>
 139 <li><code>11,11,13</code></li>
 140 <li><code>11,12,13</code></li>
 141 <li><code>11,13,11</code></li>
 142 <li><code>11,13,12</code></li>
 143 <li><code>11,13,13</code></li>
 144 <li><code>12,11,13</code></li>
 145 <li><code>12,12,13</code></li>
 146 <li><code>12,13,11</code></li>
 147 <li><code>12,13,12</code></li>
 148 <li><code>12,13,13</code></li>
 149 <li><code>13,11,11</code></li>
 150 <li><code>13,11,12</code></li>
 151 <li><code>13,11,13</code></li>
 152 <li><code>13,12,11</code></li>
 153 <li><code>13,12,12</code></li>
 154 <li><code>13,12,13</code></li>
 155 <li><code>13,13,11</code></li>
 156 <li><code>13,13,12</code></li>
 157 <li><code>13,13,13</code></li>
 158 </ul>
 159 <p>The third step (<code>off x=9..11,y=9..11,z=9..11</code>) turns <em>off</em> a 3x3x3 cuboid that overlaps partially with some cubes that are on, ultimately turning off 8 cubes:</p>
 160 <ul>
 161 <li><code>10,10,10</code></li>
 162 <li><code>10,10,11</code></li>
 163 <li><code>10,11,10</code></li>
 164 <li><code>10,11,11</code></li>
 165 <li><code>11,10,10</code></li>
 166 <li><code>11,10,11</code></li>
 167 <li><code>11,11,10</code></li>
 168 <li><code>11,11,11</code></li>
 169 </ul>
 170 <p>The final step (<code>on x=10..10,y=10..10,z=10..10</code>) turns <em>on</em> a single cube, <code>10,10,10</code>. After this last step, <code><em>39</em></code> cubes are <em>on</em>.</p>
 171 <p>The initialization procedure only uses cubes that have <code>x</code>, <code>y</code>, and <code>z</code> positions of at least <code>-50</code> and at most <code>50</code>. For now, ignore cubes outside this region.</p>
 172 <p>Here is a larger example:</p>
 173 <pre><code>on x=-20..26,y=-36..17,z=-47..7
 174 on x=-20..33,y=-21..23,z=-26..28
 175 on x=-22..28,y=-29..23,z=-38..16
 176 on x=-46..7,y=-6..46,z=-50..-1
 177 on x=-49..1,y=-3..46,z=-24..28
 178 on x=2..47,y=-22..22,z=-23..27
 179 on x=-27..23,y=-28..26,z=-21..29
 180 on x=-39..5,y=-6..47,z=-3..44
 181 on x=-30..21,y=-8..43,z=-13..34
 182 on x=-22..26,y=-27..20,z=-29..19
 183 off x=-48..-32,y=26..41,z=-47..-37
 184 on x=-12..35,y=6..50,z=-50..-2
 185 off x=-48..-32,y=-32..-16,z=-15..-5
 186 on x=-18..26,y=-33..15,z=-7..46
 187 off x=-40..-22,y=-38..-28,z=23..41
 188 on x=-16..35,y=-41..10,z=-47..6
 189 off x=-32..-23,y=11..30,z=-14..3
 190 on x=-49..-5,y=-3..45,z=-29..18
 191 off x=18..30,y=-20..-8,z=-3..13
 192 on x=-41..9,y=-7..43,z=-33..15
 193 on x=-54112..-39298,y=-85059..-49293,z=-27449..7877
 194 on x=967..23432,y=45373..81175,z=27513..53682
 195 </code></pre>
 196 <p>The last two steps are fully outside the initialization procedure area; all other steps are fully within it. After executing these steps in the initialization procedure region, <code><em>590784</em></code> cubes are <em>on</em>.</p>
 197 <p>Execute the reboot steps. Afterward, considering only cubes in the region <code>x=-50..50,y=-50..50,z=-50..50</code>, <em>how many cubes are on?</em></p>
 198 </article>
 199 <p>Your puzzle answer was <code>545118</code>.</p><article class="day-desc"><h2 id="part2">--- Part Two ---</h2><p>Now that the initialization procedure is complete, you can reboot the reactor.</p>
 200 <p>Starting with all cubes <em>off</em>, run all of the <em>reboot steps</em> for all cubes in the reactor.</p>
 201 <p>Consider the following reboot steps:</p>
 202 <pre><code>on x=-5..47,y=-31..22,z=-19..33
 203 on x=-44..5,y=-27..21,z=-14..35
 204 on x=-49..-1,y=-11..42,z=-10..38
 205 on x=-20..34,y=-40..6,z=-44..1
 206 off x=26..39,y=40..50,z=-2..11
 207 on x=-41..5,y=-41..6,z=-36..8
 208 off x=-43..-33,y=-45..-28,z=7..25
 209 on x=-33..15,y=-32..19,z=-34..11
 210 off x=35..47,y=-46..-34,z=-11..5
 211 on x=-14..36,y=-6..44,z=-16..29
 212 on x=-57795..-6158,y=29564..72030,z=20435..90618
 213 on x=36731..105352,y=-21140..28532,z=16094..90401
 214 on x=30999..107136,y=-53464..15513,z=8553..71215
 215 on x=13528..83982,y=-99403..-27377,z=-24141..23996
 216 on x=-72682..-12347,y=18159..111354,z=7391..80950
 217 on x=-1060..80757,y=-65301..-20884,z=-103788..-16709
 218 on x=-83015..-9461,y=-72160..-8347,z=-81239..-26856
 219 on x=-52752..22273,y=-49450..9096,z=54442..119054
 220 on x=-29982..40483,y=-108474..-28371,z=-24328..38471
 221 on x=-4958..62750,y=40422..118853,z=-7672..65583
 222 on x=55694..108686,y=-43367..46958,z=-26781..48729
 223 on x=-98497..-18186,y=-63569..3412,z=1232..88485
 224 on x=-726..56291,y=-62629..13224,z=18033..85226
 225 on x=-110886..-34664,y=-81338..-8658,z=8914..63723
 226 on x=-55829..24974,y=-16897..54165,z=-121762..-28058
 227 on x=-65152..-11147,y=22489..91432,z=-58782..1780
 228 on x=-120100..-32970,y=-46592..27473,z=-11695..61039
 229 on x=-18631..37533,y=-124565..-50804,z=-35667..28308
 230 on x=-57817..18248,y=49321..117703,z=5745..55881
 231 on x=14781..98692,y=-1341..70827,z=15753..70151
 232 on x=-34419..55919,y=-19626..40991,z=39015..114138
 233 on x=-60785..11593,y=-56135..2999,z=-95368..-26915
 234 on x=-32178..58085,y=17647..101866,z=-91405..-8878
 235 on x=-53655..12091,y=50097..105568,z=-75335..-4862
 236 on x=-111166..-40997,y=-71714..2688,z=5609..50954
 237 on x=-16602..70118,y=-98693..-44401,z=5197..76897
 238 on x=16383..101554,y=4615..83635,z=-44907..18747
 239 off x=-95822..-15171,y=-19987..48940,z=10804..104439
 240 on x=-89813..-14614,y=16069..88491,z=-3297..45228
 241 on x=41075..99376,y=-20427..49978,z=-52012..13762
 242 on x=-21330..50085,y=-17944..62733,z=-112280..-30197
 243 on x=-16478..35915,y=36008..118594,z=-7885..47086
 244 off x=-98156..-27851,y=-49952..43171,z=-99005..-8456
 245 off x=2032..69770,y=-71013..4824,z=7471..94418
 246 on x=43670..120875,y=-42068..12382,z=-24787..38892
 247 off x=37514..111226,y=-45862..25743,z=-16714..54663
 248 off x=25699..97951,y=-30668..59918,z=-15349..69697
 249 off x=-44271..17935,y=-9516..60759,z=49131..112598
 250 on x=-61695..-5813,y=40978..94975,z=8655..80240
 251 off x=-101086..-9439,y=-7088..67543,z=33935..83858
 252 off x=18020..114017,y=-48931..32606,z=21474..89843
 253 off x=-77139..10506,y=-89994..-18797,z=-80..59318
 254 off x=8476..79288,y=-75520..11602,z=-96624..-24783
 255 on x=-47488..-1262,y=24338..100707,z=16292..72967
 256 off x=-84341..13987,y=2429..92914,z=-90671..-1318
 257 off x=-37810..49457,y=-71013..-7894,z=-105357..-13188
 258 off x=-27365..46395,y=31009..98017,z=15428..76570
 259 off x=-70369..-16548,y=22648..78696,z=-1892..86821
 260 on x=-53470..21291,y=-120233..-33476,z=-44150..38147
 261 off x=-93533..-4276,y=-16170..68771,z=-104985..-24507
 262 </code></pre>
 263 <p>After running the above reboot steps, <code><em>2758514936282235</em></code> cubes are <em>on</em>. (Just for <span title="Well, *I* think it's fun.">fun</span>, <code>474140</code> of those are also in the initialization procedure region.)</p>
 264 <p>Starting again with all cubes <em>off</em>, execute all reboot steps. Afterward, considering all cubes, <em>how many cubes are on?</em></p>
 265 </article>
 266 <p>Your puzzle answer was <code>1227298136842375</code>.</p><p class="day-success">Both parts of this puzzle are complete! They provide two gold stars: **</p>
 267 <p>At this point, you should <a href="/2021">return to your Advent calendar</a> and try another puzzle.</p>
 268 <p>If you still want to see it, you can <a href="22/input" target="_blank">get your puzzle input</a>.</p>
 269 <p>You can also <span class="share">[Share<span class="share-content">on
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 272 ></span>]</span> this puzzle.</p>
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